An automatic chucking machine is similar to an automatic screw machine; both use spindles in production. The use of spindles, which are able to drill, bore and cut the workpiece, allows several functions simultaneously on both machines. A key difference between the machines is that the automatic chucker handles larger work, which due to its size is more often chucking work and less often bar work. The Fay automatic lathe was a variant that specialized in turning work on centers. While a screw machine is limited to around 80 mm practice, automatic chuckers are available that can handle up to 300 mm chucks. The chucks are air-operated. Many of these machines are multispindle (more than one main spindle).
Automatic chuckers are a class of machine tool specialized to narrow industry niches, such as OEM part suppliers to the automotive industry. They are limited in their economic niches to high-volume production of large parts, which tends to occur only at relatively few companies (compared to smaller work that may be done by small businesses). The market for such machine tools does not generally include local job shops or tool and die shops.
The idea of describing algebraic structures with finite-automata can be generalized from groups to other structures. For instance, it generalizes naturally to automatic semigroups.
;First (1 or L [Low]): This mode locks the transmission in first gear only. In older vehicles, it will not change to any other gear range. Some vehicles will automatically shift up out of first gear in this mode if a certain RPM range is reached in order to prevent engine damage. This, like second, can be used during the winter season, for towing, or for downhill driving to increase the engine braking effect. The "Austin Mini" automatic transmission is different in this respect - This mode locks the transmission in first gear, but the gearbox has a freewheel on the overrun. Closing the throttle after acceleration results in the vehicle continuing at the same speed and only slowing down due to friction and wind resistance. During this time, the engine RPM will drop back to idle until the throttle is pressed again. What this means is that in "First", engine braking is not available and "2" is the lowest gear that should be used whilst descending hills. The Mini's (and the 1100/1300's) 4-speed Automatic transmission was unusual in that it allowed manual selection of all forward gears, enabling the driver to "take off" from a standstill in any of the four ratios. It also provided no "Park" position.
Vehicles conforming to US Government standards must have the modes ordered P-R-N-D-L (left to right, top to bottom, or clockwise). Previously, quadrant-selected automatic transmissions often used a P-N-D-L-R layout, or similar. Such a pattern led to a number of deaths and injuries owing to driver error causing unintentional gear selection, as well as the danger of having a selector (when worn) jump into reverse from low gear during engine braking maneuvers.
Most automatic transmissions include some means of forcing a downshift (Throttle kickdown) into the lowest possible gear ratio if the throttle pedal is fully depressed. In many older designs, kickdown is accomplished by mechanically actuating a valve inside the transmission. Most modern designs use a solenoid-operated valve that is triggered by a switch on the throttle linkage or by the engine control unit (ECU) in response to an abrupt increase in engine power.
;Neutral / No gear (N): This disengages all gear trains within the transmission, effectively disconnecting the transmission from the driven wheels, allowing the vehicle to coast freely under its own weight and gain momentum without the motive force from the engine. Coasting in idle down long grades (where law permits) should be avoided, though, with many transmission designs as the transmission's lubrication pump is commonly driven by the input (engine) side, which may not provide sufficient fluid flow at engine idle speed for high-speed travel. Similarly, emergency towing (with the driven wheels of the disabled and non-running vehicle on the ground) with an automatic transmission in neutral is not permitted by the manufacturer for many vehicles. Manufacturers understand emergency situations and list limitations of towing a vehicle in neutral (usually not to exceed 55 mph and 50 miles). This is the only other selection in which the vehicle's engine may be started.
Conventionally, in order to select the transmission operating mode, the driver moves a selection lever located either on the steering column or on the floor (as with a manual on the floor, except that automatic selectors on the floor do not move in the same type of pattern as manual levers do). In order to select modes, or to manually select specific gear ratios, the driver must push a button in (called the shift-lock button) or pull the handle (only on column mounted shifters) out. Some vehicles position selector buttons for each mode on the cockpit instead, freeing up space on the central console. It follows the classic PRND gate
;Drive (D): This position allows the transmission to engage the full range of available forward gear ratios, allowing the vehicle to move forward and accelerate through its range of gears. The number of gear ratios within the transmission depends on the model, but three was initially predominant. In the 1990s four and five speeds became common. Six-speed automatic transmissions were probably the most common offering in cars and trucks from about 2010, and were still common (especially in older or less expensive models of vehicles) in 2017. However, seven-speed automatics had become available in some high-performance production luxury cars (found in Mercedes 7G gearbox, Infiniti), as are eight-speed autos in models from 2006 introduced by Aisin Seiki Co. in Lexus, ZF, Hyundai Motor Company and General Motors. From 2013 are available nine speeds transmissions produced by ZF and Mercedes 9G. In the 2017 model year Ford and General Motors introduced a 10-speed transmission.
Chrysler models with a three-speed automatic since the late 1980s have called this gear 3 while using the traditional names for Drive and Low. Oldsmobile has called second gear as the 'Super' range — which was first used on their 4-speed Hydramatic transmissions, although the use of this term continued until the early 1980s when GM's Turbo Hydramatic automatic transmissions were standardized by all of their divisions years after the 4-speed Hydramatic was discontinued.
The predominant form of automatic transmission is hydraulically operated; using a fluid coupling or torque converter, and a set of planetary gearsets to provide a range of gear ratios.
Conventionally, automatic transmissions have selector positions that allow the driver to limit the maximum ratio that the transmission may engage. On older transmissions, this was accomplished by a mechanical lockout in the transmission valve body preventing an upshift until the lockout was disengaged; on computer-controlled transmissions, the same effect is accomplished by firmware. The transmission can still upshift and downshift automatically between the remaining ratios: for example, in the 3 range, a transmission could shift from first to second to third, but not into fourth or higher ratios. Some transmissions will still upshift automatically into the higher ratio if the engine reaches its maximum permissible speed in the selected range.
In 1964, Automatic Appliances set up a 200 square meter branch at the Makati Commercial Center, the country’s first major commercial center. Pioneering the concept of appliance supermarket-ing, the store carried all of the major brands at that time: GE, Sony, Carrier, and Admiral, among others.
;Overdrive ('D', 'OD', or a boxed [D] or the absence of an illuminated 'O/D OFF'): This mode is used in some transmissions to allow early computer-controlled transmissions to engage the automatic overdrive. In these transmissions, Drive (D) locks the automatic overdrive off, but is identical otherwise. OD (Overdrive) in these cars is engaged under steady speeds or low acceleration at approximately 35 - 45 mph. Under hard acceleration or below 35 - 45 mph, the transmission will automatically downshift. Other vehicles with this selector (for example light trucks) will not only disable up-shift to the overdrive gear, but keep the remaining gears available for use of engine braking. Drivers should verify the behaviour of this switch and consider the benefits of reduced friction brake use when city driving where speeds typically do not necessitate the overdrive gear.
Automatic transmission families are usually based on Ravigneaux, Lepelletier, or Simpson planetary gearsets. Each uses some arrangement of one or two central sun gears, and a ring gear, with differing arrangements of planet gears that surround the sun and mesh with the ring. An exception to this is the Hondamatic line from Honda, which uses sliding gears on parallel axes like a manual transmission without any planetary gearsets. Although the Honda is quite different from all other automatics, it is also quite different from an automated manual transmission (AMT).
The Browning Automatic Rifle (BAR) was one of the first practical automatic rifles. The BAR made its successful combat debut in World War I, and approximately 50,000 were made before the war came to an end. The BAR arose from the concept of "walking fire", an idea urged upon the Americans by the French who used the Chauchat light machine gun to fulfill that role. The BAR never entirely lived up to the designer's hopes; being neither a rifle nor a machinegun. "For its day, though, it was a brilliant design produced in record time by John Browning, and it was bought and used by many countries around the world. It was the standard squad light automatic of the U.S. infantry during World War II and saw use in every theater of war." The BAR was praised for its reliability and stopping power. "The US forces abandoned the BAR in the middle 1950s, though it was retained in reserve stocks for several years; it survived in smaller countries until the late 1970s."
;Second (2 or S): This mode limits the transmission to the first two gear ratios, or locks the transmission in second gear on Ford, Kia, and Honda models. This can be used to drive in adverse conditions such as snow and ice, as well as climbing or going down hills in winter. It is usually recommended to use second gear for starting on snow and ice, and use of this position enables this with an automatic transmission. Some vehicles will automatically shift up out of second gear in this mode if a certain RPM range is reached in order to prevent engine damage.
That store evolved into a 3,400-square-meter showroom called Automatic Centre, which opened in 1977. It introduced Blims Fine Furniture which became an integral section of the store. To date, Automatic Centre has 19 stores across the country, with stores situated at the country's top shopping malls.
Usually, Park (P) is one of only two selections in which the car's engine can be started, the other being Neutral (N). This is typically achieved via a normally open inhibitor switch (sometimes called a "neutral safety switch") wired in series with the starter motor engagement circuit, which is closed when P or N is selected, completing the circuit (when the key is turned to the start position). In many modern cars and trucks, the driver must have the foot brake applied before the transmission can be taken out of park. The Park position is omitted on buses/coaches (and some road tractors) with automatic transmission (on which a parking pawl is not practical), which must instead be placed in neutral with the air-operated parking brakes set.
Hydraulic automatic transmissions consist of three major components: